1. the state of being born to parents who are not married to each other
Usage: legal; formal
2. the quality of being contrary to or forbidden by law
Usage: legal
3. the quality of being unreasonable or unacceptable
Usage: formal

Examples

• The law no longer discriminates against children based on illegitimacy.
• Birth certificates from that era often indicated illegitimacy.
• The court questioned the illegitimacy of the contract.
• His claim to the throne was challenged due to illegitimacy.
• The illegitimacy of the government’s actions sparked protests.
• Modern society has largely moved past concerns about illegitimacy of birth.